Apparatus for manufacturing sheets and other articles from plastic materials



S. S. WILSON Filed Dec. '7, `192.3

Patented Dec. 30, 1924.

UNITED STATES PATENT OFFICE.

SAMUEL SCOTT'WILSGN, OF'MEYERTO'N, TRANSVAAL, SOUTH AFRICA.

APPARATUS FOR MANUFACTURING SHEETS AND OTHER ARTICLES FROM PLASTICMATERIALS.

Applica-tion filed December vv7, 1923.

To all whom# may concern.'

Be it known that I, SAMUEL SCOTT TIL- soN, a subject ofthe King of GreatBritain, and resident of Meyerton, Transvaal Province, Union of SouthAfrica, have invented .a certain new and useful Improvement in 'theinvention can also be adapted to the manufacture or production ofyarticles or .products of other shape or configuration from suchmaterials.

In one method of manufacturing sheets., etcetera, from a mixtureofasbestos, vPortland cement and water, the mixture is spread on a table,slab or mould made from material which Ahas -a high absorptive capacityfor water, such as plaster of Paris.

The present improvements appertain to an apparatus in which such a slab,table or mould is employed, and have for one object to combine therewithheating means which will facilitate 'the process of manufacture Ibyensuring a quicker drying of the material after it has been spread orapplied Vto the surface of the slab, table or mould. Another object isIto prevent the cement or equivalent ingredient of the mix-ture from`coming directly into `contact with :the surface `of the porous slab,table or mould, so as to maintain the maximum absorptive capacity. A.further object is to construct the apparatus in such a way that theslab, etcetera, can he used practically continuously, by utilizing bothsides thereof, and to that end providing means whereby it can be readilyVinverted. A still further object is to construct and .arrange thevarious parts of the .apparatus `to simplify and facilitate Aproduction`and thereby reduce the cost of manufacture of the sheets, etcetera,with the aid thereof.

As a result of the rapid formation and drying of the sheets, etcetera, amixture containing a higher percentage of asbestos Serial No. 679,248.

can be used than with the existing slabs and in that way a lightervsheet can be made.

The invention will be more particularly explained in connection with theaccompany- Iing drawings, wherein,-

Fig. 1 isa part-sectional -side elevation of the apparatus designed foruse in the -production of sheets.

Fig. 2 is a `part-sectional plan of the same, and

Fig. 3 isa `plan view, drawn to a reduced scale, of the `carrie-r and`support for retaining the sheet ron the slab or the like while thelatter is being inverted, and for subsequently removing it therefrom.

In the drawings the numeral 1 denotes the slab, table or mould which ismade of :plaster of Par-is or other similar material or mixture of highabsorptive capacity f'or water. The slab, etcetera, 1 is made ofappropriate dimens-ions and is carried in a metal framework showncomprising the two rectangular angle iron frames 2, 3 the ends of whichare each connected by means of a .strap or plate t-see Fig. 2. To theframe 2, 3, at .oppositesides thereof, are ybolted .or

otherwise suitably fixed plates .5, 6, to which,

etcetera, is rotatably supported; 11, 12, be-

ing the bearings in which the trunnions are IJournalled, a-nd 13, 14,,the pedesta-ls vor foundations upon which the bearings l1,

12, are arranged at a sui-table working height.

For the purpose of lheating the slab,

etcetera, a pipe 15, shaped into the formof a attened coil or a doubleZig-zag structure is embedded therein, yand one end, 16, of the pipe 15,opens into the one hollow `trunnion .9, whilst ythe other, 17, opensinto the other hollow trunnion 10. Theends 16, '17, of the pipe 15 maybe fixed in the plates 5, 6, Arespectively, by the nuts 18, 19. Thehollow trunnion 9 may serve as the inlet -to the flattened coil 15 andthe other hollow trunnion 10 serve as the outlet. rlhe steam or hotfluid supply pipe 2O passes through a. stufling box and `gland 21 intothe hollow trunnion 9; 22 being a `nut for preventing withdrawal of thepipe 20. 23 is the `outlet pipe from vthe flattened coil which .pipe

' upon the slab,etcetera, 1.

shown comprising two rigid side members v vided.

23 passes through a gland 24 arranged at the ,outer end of the hollowtrunnion 1Q, the gland 24 being of the same construction as gland 21. fp In order to support and steady the slab, etcetera, 1 in its normalhorizontal position,

which is the position in which it is placeol when forming a sheet,etcetera, thereon, movable wedge-shaped rests or stops 25, 26, placed atopposite sides of the slab, are pro- IThese rests 25, 26, are shownarranged in guides 27, 28, fixed on the foundations 13, 14, at oppositesides of the bearings 11, 12. The rests or stops 25, 26, are withdrawnfrom their guides 27, 28, when it is desired to invert the slab,etcetera', 1, as

hereinafter explained. y

In order to impart the desired shape to the sheet, etcetera, anddetermine its thickness, a loose removable metal frame is employed,

which is made of a size and shape to correspond to the sheet, etcetera,to be formed This frame 1s areshown placed at the ends of the frame,

parallel to the members 31,32, and next the inner ends ofthe smallpieces 34, so that said pieces 34 serve asstops for the members 36, 37in the direction of the ends ofthel frame. The thickness of the members'29, 30,

and 36, 37, determines the thickness'of-the sheet, etcetera, which ismade in the frame, and the size of' the sheet, etcetera, is equal to thearea of the space enclosed between the inner edges yof said members.'This construction of the frame facilitates the operation of removing theframe after the sheet,

etcetera, has'been formed, and the subse-` quent removal of the sheetfrom the slab or table.

The upper surface of the slabr or table 1 is completely covered with apiece of jute canvas 38, or other suitable canvas or woven material of asuitable texture, and upon said canvas covering 38, there ispreferablyflaid a sheet of paper 39' or other suitable material which,While readily admitting of the passage through it of water, will preventthe passage through it of the fine solid mate rial or the cement'ofthemixture.

or moulded is placed directly uponthe paper covering 39. Alternatively,the paper 39 may be dispensed with and the table 1 cov- The i 'frame inwhich the sheet, etcetera, is made;

ered with apiece of coarse woven fabric, such as hessian, to which athin layer of a mixture of French chalk and plaster of (Paris isapplied, the piece of jute canvas or the like being placed upon saidhessian or the like.. v

The material from which the sheet is to be made is more or less roughlyspread upon the 'surface ofthe paper 39, inside the frame, and it isthen formed into an even layer or thickness by suitable means, as forexample, by means of a suitable heavy roller 40, comprising an outermetal pipe or tube filled with concrete orother suitable weighty ma-lterial 41, and closed at the ends with cover plates 42V. The roller isprovided with a central rod 43 which serves as a handle at each endprojecting beyond the sides of the frame of the slab or table. Theroller near its ends rests and rolls on the members 29, 30 of the frame.v

After the material has been roughly spread on the slab or table, it isrolled level by moving the roller backwards and forwards, any surplusmaterial being thereby worked to the ends of the frame from which it canbe removed in any4 suitable manner, as for example, by means ofl atrowel or the li e.

After the sheet has been formed,` the frame comprising the members 29,30, 31, 32, is removed, and the separate or loose members 36, 37, arethen taken away. The formed sheet is now secured on the surface of theslab or table by means of a carrier and support shown-see Figs. 1 and i3-constructed of a suitable number of parallel members or slats 44connected together by a suitable number of other members 45 placed atright angles thereto. Means are provided for attaching this support andcarrier to the sides of the frame of the slab or table, and for thispurpose each of said sides has hingedly attached toit an eyebolt 46,which are adapted to engage in the bifurcated ends 47 of the centralparallel member 45; 48 are wing nuts on the ends of the eyebolts 46 forclamping'the carrier in position over the sheet. Vhen the slab or tableis inverted the sheet. lies upon the carrier and support so that thelatter serves as a convenient vehicle for transporting it' to any Ydesired place. The loosening of the Wing nuts 48 allows the eyebolts46to be disengaged from the bifurcated ends 47 of the centralparallelmember 45, which permits the carrier, together with the sheet,to be lowered and removed.

The eyebolts" 46 lare pivotally mounted on pins 49 which are carriedbetween two an` gleA iron pieces 50 fixed to the angle iron members 2,'3, of the frame. The pins 49 are placed centrally of the depth'ofthetable or slab 1, so that the eyebolts 46 can be used for fixing thecarrier and support on either face of the slab or table. By attachingthe angle iron pieces to the members 2, 3, they serve to stiffen andstrengthen the framework carrying the slab or table.

lVhat I claim as my invention and desire to protect by Letters Patentis:-

l. An apparatus of the nature indicated, including a table made ofplaster of Paris and heating means embedded in said table, as set forth.

2. An apparatus of the nature indicated, including a table made ofplaster of Paris and heating means in the form of a flattened coilembedded in said table, as set forth.

3. An apparatus of the nature indicated,

- including a table made of plaster of Paris,

said table being adapted to be rotated in order to invert it, set forth.

et. An apparatus of the nature indicated, including a table made ofplaster of Paris, said table being adapted to be rotated in order toinvert it, and removable rests for retaining the table in its horizontalor working position, as set forth.

5. An apparatus of the nature indicated, including a table made ofplaster of Paris, and heating means embedded in said table, said tablebeing adapted to be rotated in order to invert it, as set forth.

6. ./Ln apparatus of the nature indicated, including a table made ofplaster of Paris, said table being adapted to be rotated in order toinvert it, the means for permitting of the table being invertedcomprising trunnions provided at opposite sides of the table andbearings for said trunnions, and heat-ing means embedded in the table,as set forth.

7. An apparatus of the nature indicated, including a table made ofplaster of Paris, heating means in the form of a fiattened coil embeddedin said table, means for permitting of the table being` inverted, saidmeans comprising trunnions provided at opposite sides of the table andbearings for said trunnions, the trunnions being of hollow constructionand communicating with the fiattened coil, and means for introducing theheating medium into one trunnion and for withdrawing said medium fromthe other trunnion, as set forth.

8. An apparatus of the nature indicated, including a table made ofplaster of Paris` heating means embedded in said table,l said tablebeing adapted to be rotated in order to gig invert it, and porous mediaarranged upon the workin@l surface of said table, as set forth.

9. An apparatus of the nature indicated, including a table made ofplaster of Paris, heating means embedded in said table, and anappropriately shaped iframe arranged upon said table, said frame beingprovided with flexible ends and rigid sides and separate or loose endmembers arranged inside said frame, as set forth.

l0. An apparatus of the nature indicated, including a table made ofplaster' of Paris, heating means embedded in said table, said tablebeing adapted 'to be rotated in order to invert it, a carrier andsupport for the sheet or product, and means provided on the table fordetachably securing the carrier and support on either working surface ofthe table, as set forth.

1l. An apparatus of the nature indicated, including a table made ofplaster of Faris, heating means in the forni of a flattened Coilembedded in said table, means for permitting of the table beinginverted, said means comprising trunnions provided at opposite sides ofthe table and bearings for said trunnions, the trunnions being of hollowconstruction and communicating with the flattened coil, means forintroducingl the heating medium into one trunion and for withdrawingsaid inediuin from the other trunnion, porous media arranged on theworking surface of the table, upon which media the material is mouldedor formed, said porous media consisting of a sheet of canvas and asuperimposed sheet of paper, an appropriately shaped frame arranged uponthe table, said frame being provided with flexible ends and rigid sidesand separate or loose end members arranged inside said frame, a carri ror support for the sheet or product, and means provided on the tabie fordetachably securing the carrier or support on either working surface ofthe table, as set forth.

In testimony whereof l have signed my name to this specification in thepresence of two subscribing witnesses.

Srr/IUEL SCOTT VILSON. Witnesses LiLLiAN A. GiNsnnnG, An'rirtn:TrionrsoN.

